Are there any people who are using a watermeter powered by a powerbank? For example the homewizard one? Ifso how long does the powerbank last?
I posted this question directly into the Homewizard thread and never got an answer 
Note, Homewizard watermeter has a battery option with special ‘economy’ mode with 4 updates / day and should last a year, but it still measures and saves data every 5 minutes. Not too bad. And maybe it runs for 6+ months with rechargable ones.
While Sharkys didn’t get a response, no one who read his Q seems to have tested it irl. So I felt free to share a theory.
With a powerbank to USB-C, it will be ‘seen’ as PSU, and keep the wifi connected, so it would use 0.5Wh to 1Wh max?
Let’s say it’s 0.5Wh
P = U * I
0.5W = 5V * 0.1A
→ a 20Ah PB then would last 20 / 0.1 = 200hrs max.
From https://helpdesk.homewizard.com/nl/articles/6287312-de-watermeter-gebruiken-op-batterijen :
With 2x CR123A batteries, the Water Meter will last a year on battery power. On batteries, the Water Meter collects data every 5 minutes and then sends it to the app 4x a day. Between these times, it is in power-saving sleep mode.
Optionally, you can press and hold the button on the Water Meter for 1 second to immediately send the collected data (this will reduce battery life).
On battery power, the Water Meter can accurately measure up to 35 liters per minute. 30 liters is sufficient to measure a shower and 2 other water sources at the same time, such as a tap or the flushing of a toilet. If more water is used, such as in larger households with multiple showers, the standard reading rate of the Water Meter may not be sufficient. We recommend running the Water Meter on USB-C power or increasing the measurement speed (this will reduce battery life).
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